Two fundamentally different mechanisms by which unconscious information impairs behavioral performance: Evidence from fMRI and computational modeling

• Published in: NeuroImage (Orlando, Fla.) Fla.), 2024-08, Vol.297, p.120719, Article 120719
• Main Authors: Wang, Yongchun, Di, Meilin, Li, Ya, Liu, Peng, Zhao, Jingjing, Wang, Yonghui
• Format: Article
• Language: English
• Subjects: Behavior; Cognition; Computer applications; Cortex (parietal); Drift-diffusion model; fMRI; Functional magnetic resonance imaging; Hypotheses; Information processing; Motor inhibition; Motor task performance; Negative compatibility effect; Object updating; Parietal lobe; Sensorimotor integration; Sensorimotor system; Visual stimuli
• ISSN: 1053-8119; 1095-9572; 1095-9572
• DOI: 10.1016/j.neuroimage.2024.120719

•There are two ways in which unconscious stimuli impairs behavioral performance.•For relevant stimuli, the impairment is derived from visual perceptual processing.•For irrelevant stimuli, the impairment is derived from motor response processing. It is increasingly clear that unconscious information impairs the performance of the corresponding action when the instruction to act is delayed. However, whether this impairment occurs at the response level or at the perceptual level remains controversial. This study used fMRI and a computational model with a pre-post design to address this elusive issue. The fMRI results showed that when the unconscious information containing strong stimulus-response associations was irrelevant to subsequent stimuli, the precuneus in the parietal lobe, which is thought to be involved in sensorimotor processing, was activated. In contrast, when the unconscious information was relevant to subsequent stimuli, regardless of the strength of the stimulus-response associations, some regions in the occipital and temporal cortices, which are thought to be involved in visual perceptual processing, were activated. In addition, the percent signal change in the regions of interest associated with motor inhibition was modulated by compatibility in the irrelevant but not in the relevant stimuli conditions. Modeling of behavioral data further supported that the irrelevant and relevant stimuli conditions involved fundamentally different mechanisms. Our finding reconciles the debate about the mechanism by which unconscious information impairs action performance and has important implications for understanding of unconscious cognition.